finding the location of a robot

Hi,
Am building a land rover for which i got to send the location of the robot to the base station..which sensor can i use??a sonar??am right now using atmega8..wil it be able to handle this??

pls help me out...

If you want location, I guess you'd want GPS. But the atmega8 is really low powered; I've seen servos with more processing power.